1. PSYC 206
Lifespan Development
Bilge Yagmurlu

2. I. Inheriting Culture Culture:
The use of material and symbolic tools that accumulate over time, are passed on through social processes, and provide resources for the developing child.

3. The Tools of Culture Material tools:
Includes physical manufactured objects and observable patterns of behavior

4. Tools of Culture Symbolic tools:
More abstract, including systems of knowledge, beliefs, and values.

5. Process of Cultural Inheritance
Culture is inherited through social processes
Use of culture’s tools
Social enhancement
Imitation
Explicit instruction

6. Process of Cultural Inheritance
Culture is inherited through social processes.
Use of symbolic communication
Unique to humans
Learning about things not immediately present and about abstractions

7. Complexity of Culture Cumulative Cultural Evolution
Cultures continue to evolve because they are complex.
Examples of Variations in tool usage
Material Tools
Symbolic Tools

8. Biological Evolution Heredity
Transmission of biological characteristics from one generation to the next

9. Biological Evolution Genes: Genotype: Phenotype:
Contains instructions that guide the formation of the individual’s traits
Genotype:
The exact genetic makeup
Phenotype:
The observable trait, behavior, and psychological traits

10. Natural Selection
The process whereby individuals with phenotypes well adapted to the local environment survive and reproduce to a greater extent than individuals with less well- adapted phenotypes, preferentially passing on the genotypes associated with the better-adapted phenotypes.

11. Natural Selection
Examples: Genotypic variations contribute to phenotypic contributions
Baby-talk

12. Heritability
The proportion of phenotypic (observed) variance in a given population that is due to genetic variance.
Example:
H of 20 = 20% GV and 80% Environmental

13. Plasticity of the Trait
Phenotypic plasticity
The degree to which the phenotype is open to influence by the environment, rather than by genotype.
Traits with high plasticity
Traits with little plasticity
Example

14. Plasticity of the Trait
Phenotypic canalization
A trait is called “canalized” when it follows a strictly defined path, regardless of most environmental and genetic variations.
Example:

15. Plasticity of the Trait
Phenotypic canalization
“auto-regulatory mechanism” 15

16. Heritability
Assessed through kinship studies: Behavioral Genetics Methods
Family Studies
Twin Studies
Adoption Studies

17. Genetic Inheritance Chromosome Ovum contains 23 Sperm contains 23
Zygote contains 46 or 23 pairs

19. Genetic Inheritance
Chromosomes containing DNA (deoxyribonucleic acid) are situated in the nucleus of a cell.
Genes are functional units of heredity which are composed of DNA.

20. Human Genome Project
Genome is the set of complete instructions for making an organism, containing all the genes in that organism
Completed in 2003, the HGP was a 13-year project coordinated by the U.S. with contributions from UK, Japan, France, Germany, China, etc.
Some goals:
identify all the approximately 20,000-25,000 genes in human DNA
transfer related technologies to the private sector
address the ethical, legal, and social issues (ELSI) that may arise 20

21. Heritability Assessed through kinship studies:
Family Studies: Studies that correlate degree of genetic overlap among family members with degree of similarity in developmental outcomes

22. Heritability Family Studies
Example: a disorder might be described as “running in a family” if more than one person in the family has the condition
Example: “Anxiety disorders run in families”:
role of inheritance and environment 22

23. Heritability: Twin Studies
Identical
twins
Fraternal
Same
sex only
Same or
opposite sex
Identical Twins
develop from a single fertilized egg that splits in two, creating two genetically identical organisms
Fraternal Twins
develop from separate eggs
genetically no closer than brothers and sisters 23

24. Heritability Twin Studies: Monozygotic Twins (100% shared genes)
Dizygotic Twins (50% shared genes)
If identical twins are more alike than fraternal twins, then the increased similarity can be due to genetic influences
Relies on the “equal environments assumption” 24

25. Heritability
Twin Studies:
Equal environments assumption 25

26. Phenomena of Niche Construction:
Refers to how behaviors, activities, and choices of individuals actively shape and modify the environment in which they live 26

27. Heritability Adoption Studies:
Examine the correlations between adopted children and their adoptive parents, or adopted children and their genetic parents 27

28. Adopted / Separated Twins
Investigators have also studied identical twins who were separated early in life and reared apart.
Any similarities in traits between them should be primarily genetic and should permit a direct estimate of heritability. 28

29. III. The Coevolution of Culture and Biology
the process that emerges from the interaction of biological evolution and cultural evolution.

30. III. The Coevolution of Culture and Biology
Example
The skeletal structure of humans and other primates are highly similar. But there are two main differences that might have caused early humans to develop high technology:
1) bipedalism
2) using thumb in opposition with the other four fingers 30